March is a good time to celebrate the contribution that Corning Glass Works made in creating Palomar Observatory's 200-inch mirror. 77 years ago this month they made their first attempt at casting the 200-inch. It was unsuccessful, but you can check out a previous post on it here.
If you get the chance you really should see the first disc, which is on display at the Corning Museum of Glass. You can also check out their Mirror to Discovery exhibit, at which can be seen until the end of October in their Rakow Library.
Our "photo" this week is a detailed drawing of Corning's factory as it was set up for casting the 20-ton disc. Click on the image or this link to see a huge and richly detailed version of the drawing from the June 1934 issue of Popular Science Monthly.
This month also marks the 75th anniversary of the beginning of the trip westward for their second, successful disc. I will be posting other images this month that fit with both anniversaries.